This invention relates to a self penetrating boat anchor for engaging the bottom beneath a lake or other body of water and which penetrates the bottom in response to being dragged by the boat. More particularly, the invention involves a self penetrating boat anchor having flukes that pivot with respect to the shank to permit the flukes to dig into the lake bottom when the anchor is dragged, when either side of the anchor is in engagement with the lake bottom.
Boat anchors are formed in various configurations for the purpose engaging the bottom beneath the body of water so that the anchor can hold itself to the bottom while it""s anchor chain and line extend latterly and upwardly to the surface of the water and hold a boat or other floating object in a relatively stationary position.
One of the more popular styles of boat anchors is the Danforth anchor that is relatively lightweight for its size, and is useful for anchoring small boats. The anchor has a shank connected at one of its ends to an anchor chain, the other end of the shank is pivotally connected to a stock and a pair of flukes. The stock extends normal to the shank, and the flukes straddle the shank and are connected to the stock so that their pointed ends can pivot with respect to the shank and penetrate the lake bottom. When the anchor chain attempts to drag the anchor along the lake bottom, the flukes can pivot with respect to the stock, to extend at a downwardly sloped angle that causes them to penetrate the surface of the lake bottom, thereby holding to the bottom. This tends to terminate the lateral movement of the anchor, thereby restraining the movement of the boat or other floating objects at the surface of the water.
The anchors are made so that the pair of flukes that straddle the shank are rigidly connected to each other by a common stock. The stock extends laterally at the base of the shank and flukes, and the stock is pivotally connected to the shank. With this arrangement, the anchor can fall from the boat to the lake bottom, and then tilt in either direction until it""s shank lies flat upon the lake bottom, and the flukes will have the opportunity to form an angle with respect to the shank, to extend downwardly into the lake bottom as the shank is being pulled across the lake bottom by the boat.
The prior art self penetrating boat anchors must be much heavier than the weight of water so as to the sink to the bottom of the lake and to resist upward lifting forces that might be caused by movement of the water. It is important that the shank of an anchor be of high specific gravity so that it will tend to lie flat upon the lake bottom even in response to being dragged by the boat to which it is tether. If the shank is of lightweight, low specific gravity construction it will be more likely to tilt upwardly as it is being dragged by the boat, so that it""s flukes will have less opportunity to engage and penetrate the lake bottom.
Likewise, the shank must be of very strong material so that it can withstand the various forces applied to it by the boat dragging the anchor or forcing the anchor into the lake bottom, and to resist deterioration from various obstructions that might be encountered at the lake bottom.
Likewise, the stock of the boat anchor must be of very strong material so as to resist the forces applied to it under the same circumstances as the shank, and also being able to penetrate that lake bottom. The use of ferrous material for both the shank and the stock is desired for strength and weight purposes, so that the stock and shank can be of relatively small cross sectional area for the ability to penetrate the lake bottom.
In addition, the prior art has taught the use of ferrous materials, such as stainless steel, for use in all parts of a self-penetrating boat anchor, including the flukes, the crown, and the aforesaid elements. This provides the anchor with adequate weight and strength to perform its desired functions.
While the prior art anchors have been successful in function, there is a problem with the weight of an anchor particularly when the anchor is being handled at the level of the boat, by lifting the anchor out of the water for placement in the boat or lifting the anchor out of the boat for placement in the water. Obviously, the heavier and more massive the anchor, the better holding power it achieves with respect to the lake bottom, but the more difficult it is handle by the personnel in the boat, and the excessive weight of the anchor, together with it""s shape, is hazardous to the boat with regard to marring scarring, or even rupturing the deck and/or bulk heads of the boat.
Applicant addresses the above noted problems by providing a bi-metal, lightweight self-penetrating boat anchor that utilizes different metals for different parts of the anchor.
Briefly described, the present invention provides a bi-metal, light weight self penetrating boat anchor for use with boats in which the anchor, it""s chain and line are expected to be handled manually, and in which the light weight of the anchor is desirable when the anchor is being man handled.
The anchor includes the conventional shank that is pivotal with respect to the stock, flukes and crown of the anchor. The flukes, stock and crown are assembled so as to be rigidly attached to one another, whereas the shank is pivotal with respect to these elements, to extend at an acute angle to either side of the flukes. In the embodiment of the invention illustrated, the crown limits the pivotal movement of the flukes, with respect to the shank to an angle of 35xc2x0 to either side of the shank. This angle can be increased or decreased as might be desired by reshaping the crown of the anchor, but must be limited to less than a right angle for proper penetration into the lake bottom.
The flukes of the anchor are substantially flat, with a strengthening rib of each fluke facing the shank. The flukes are necessarily broad so as to be able to engage the lake bottom with sufficient cross sectional area so as to perform their anchoring functions. Thus, the volume of material embodied in the flukes usually is greater than the volume of material embodied in the other elements of the anchor assembly.
Likewise, the crown that functions to raise the pivotal ends of the flukes away from the lake bottom so that the pointed distal ends can penetrate the lake bottom comprises a mass of material of sufficient volume. However, it is not necessary that either the flukes or the crown be fabricated of heavier metals because of the manner in which they function on the lake bottom. In contrast, however, the shank and the stock must be made of very strong and dense materials so that the weights and strengths of these parts are used in the function of an anchor. For example, the shank must be heavy in order to lie parallel to the surface of the lake bottom, thereby giving the flukes the opportunity to droop from their pivoted ends to their pointed distal ends toward engagement with the lake bottom. When the anchor is dragged by it""s chain and line extending to the boat, the heavy shank tends to remain flat on the lake bottom until the boat is almost over the anchor and the anchor is lifted upwardly toward the boat. This gives the flukes and opportunity to penetrate the lake bottom. Likewise, the stock must be of strong material so as to withstand the forces normally applied to it when being dragged through the lake bottom or into engagement with obstructions with on the lake bottom. Moreover, both the shank and stock should be of relatively thin profile so that they also can penetrate the lake bottom in response to their movements imparted by the boat attempting to drag the anchor.
However, the flukes and crown of the invention that should be formed with more cross sectional surface area are fabricated of lighter weight material than the stock and shank, such as Aluminum, Magnesium or Titanium. This allows the anchor to be lighter in weight while retaining more mass in the stock and shank where it is important to retain the weight.
Thus, it is the object of this invention to provide an improved a self penetrating boat anchor of light weight that function adequately to anchor a boat or other floating objects, yet is of lighter than conventional weight for ease and handling and storing.
Another object of this invention is to provide a self penetrating boat anchor that includes parts thereof that are of dense, heavy metals that utilizes the weight of the metals for enhancing the functions of an anchor, and utilizes lighter weight metals in those parts of the anchor that do not require the parts to be of heavy weight for proper functioning of the anchor.